Field of the Invention
The present invention relates to a technology concerning three-dimensional (3D) measurement, and particularly relates to a technology for assessing an image pair used for 3D measurement from plural captured images.
Description of the Related Art
There has been known a method for performing 3D measure in which an imaging position is moved relatively to an object to be measured to acquire plural captured images by a capturing device and an image pair is made using the plural captured images (motion stereo method). In the motion stereo method, if the object to be measured is large, the 3D measure is hard to perform with only one image pair in some cases. Examples of the method of the 3D measurement for the object to be measured that is a large one like this include a method in which the 3D measurement is performed by making plural image pairs and synthesizing 3D data made from the respective image pairs to create one piece of large 3D data.
In the case of making the plural image pairs from the plural captured images, if a man/woman grasps the image pair and information on the image pair grasped by the man/woman is processed by software, work is troublesome and the image pair is likely to be erroneously selected.
Japanese Patent Application Laid-Open No. 2009-014629 (hereinafter referred to as PTL 1) describes a technology in which a captured image includes a plurality of frames, and a feature point of an object to be imaged (considered to correspond to the object to be measured in the present invention application) in the captured image is tracked to determine true or false of a stereo pair (considered to correspond to the image pair in the present invention application) on the basis of a vertical parallax for the feature point.
Japanese Patent Application Laid-Open No. 2009-014628 (hereinafter referred to as PTL 2) describes a technology in which a captured image includes a plurality of frames, and a feature point of an object to be imaged in the captured image is tracked to determine true or false of a corresponding point corresponding to the feature point and select a stereo pair.
Japanese Patent Application Laid-Open No. 2012-124554 (hereinafter referred to as PTL 3) describes a technology in which capturing is controlled via a CPU or the like to acquire a pair of images while azimuth information and posture information of a camera obtained from an azimuth sensor and acceleration sensor are displayed on a liquid crystal panel to support capturing carried out by a user in a state where an optical axis direction and a posture condition in a horizontal direction between two images are not relatively deviated.
Japanese Patent Application Laid-Open No. 2001-317915 (hereinafter referred to as PTL 4) discloses a technology relating to 3D measuring device which includes capturing means for imaging a measured object, first feature point specifying means for specifying a feature point on an image in which the measured object is captured by the capturing means, distance measurement means for measuring a distance to the feature point on the measured object specified by the feature point specifying means, second feature point specifying means for specifying a point on the measured object corresponding to a feature point on an image in which the measured object is captured at a first imaging position as a feature point on an image in which the measured object is captured at a second imaging position by the capturing means, and arithmetic means for finding a relative position and angle between the first imaging position and the second imaging position from the feature points on the images in which the measured object is captured at the first imaging position and the second imaging position and the distances to the feature points measured at the imaging positions by the distance measurement means.